近日，意大利山地急诊医学研究所Giacomo Strapazzon团队研究了呼吸气体转移延迟窒息装置对雪崩掩埋者生存率的影响。相关论文于2025年10月8日发表在《美国医学会杂志》上。

被雪崩严重掩埋的人通常在35分钟内死于窒息，这往往使及时救援变得不可能。制定延迟窒息的新策略对提高生存率至关重要。

为了研究一种可将雪崩碎片中的气流输送到用户气道且无需补充氧气或面罩的新型雪崩安全装置的有效性，研究组进行了一项随机、盲法临床试验，由4个机构组织，于2023年1月至3月在意大利的1个实地地点进行。招募了年龄在18至60岁之间的健康志愿者。试验参与者在俯卧位置被至少50厘米的雪覆盖时进行了关键的雪埋模拟。在整个模拟过程中持续监测重要参数，以确保参与者的安全并收集生理数据。

参与者被随机分为安全装置组（使用Safeback SBX装置）或对照组（使用假装置）。安全装置组完成了一项非盲法控制，35分钟后仍被掩埋的参与者被无缝转移到假装置上。主要结局指标是在35分钟的监测期间，通过脉搏血氧仪（SpO₂）测量到氧饱和度低于80%（事件）的时间，比较干预组和对照组。次要结局包括雪中不同距离的氧气和二氧化碳浓度。

在36名随机参与者中，24人完成了试验并被纳入最终分析。中位（IQR）年龄为27岁（25-32岁），男性13例（54%）。安全装置组中位（IQR）掩埋时间为35.0（35.0 ~ 35.0）分钟，无事件发生；对照组中位（IQR）掩埋时间为6.4（4.8 ~ 13.5）分钟，共发生7起事件。安全装置组因SpO₂小于80%而终止的风险显著降低（log-rank和Breslow检验均为P<0.001）。在安全装置组和对照组的同一点，气穴中的二氧化碳分别为1.3% （95% CI, 1.0%-1.6%）和6.1% (95% CI, 5.1%-7.1%)，氧气分别为19.8% （95% CI, 19.5%-20.1%）和12.4% （95% CI, 11.2%-13.5%）。

研究结果表明，用户携带的雪崩安全装置可以将雪崩碎片中的气流输送到用户的气道，而不需要补充氧气，从而延迟了模拟关键掩埋期间的严重低氧血症和高碳酸血症。

附：英文原文

Title: Respiratory Gas Shifts to Delay Asphyxiation in Critical Avalanche Burial: A Randomized Clinical Trial

Author: Frederik Eisendle, Giulia Roveri, Simon Rauch, yvind Thomassen, Tomas Dal Cappello, Jrg Assmus, Sandro Malacrida, Tobias Kammerer, Jürg Schweizer, Nicola Borasio, Viviane Drck, Markus Falk, Marika Falla, Nicola Fruzzetti, Matilde Maxenti, Sigurd Mydske, Gian Mauro Sasso, Giovanni Vinetti, Bernd Wallner, Guttorm Bratteb, Hermann Brugger, Giacomo Strapazzon

Issue&Volume: 2025-10-08

Abstract:

Importance  People who are critically buried by an avalanche typically die of asphyxia within 35 minutes, often making timely rescue impossible. The development of new strategies to delay asphyxiation is crucial to improve survival rates.

Objective  To investigate the efficacy of a novel, user-carried avalanche safety device that delivers airflow from avalanche debris to the user’s airway without requiring supplemental oxygen or a mouthpiece.

Design, Setting, and Participants  This randomized, blinded, clinical trial was organized by 4 institutions and conducted at 1 field location in Italy from January to March 2023. Healthy volunteers aged 18 to 60 years were enrolled. Trial participants underwent a critical snow burial simulation while in a prone position covered by at least 50 cm of snow. Vital parameters were continuously monitored throughout the simulation to ensure participant safety and to collect physiological data.

Interventions  Participants were randomized to the safety device group (using the Safeback SBX device) or the control group (using a sham device). The safety device group completed an unblinded control in which the participants who remained buried after 35 minutes were seamlessly transferred to the sham device.

Main Outcomes and Measures  The primary outcome measure was the time to oxygen saturation as measured by pulse oximetry (Spo2) less than 80% (event) during 35 minutes of monitoring, comparing intervention and control groups. Secondary outcomes included oxygen and carbon dioxide concentrations at different distances in the snow.

Results  Of 36 randomized participants, 24 performed and completed the trial and were included in the final analysis. The median (IQR) age was 27 (25-32) years, and 13 (54%) were male. In the safety device group, the median (IQR) burial duration was 35.0 (35.0-35.0) minutes and there were no events; in the control group, the median (IQR) burial duration was 6.4 (4.8-13.5) minutes and there were 7 events. The safety device group had a significantly lower risk of termination due to Spo2 less than 80% (P<.001 for both log-rank and Breslow tests). Carbon dioxide in the air pocket was 1.3% (95% CI, 1.0%-1.6%) vs 6.1% (95% CI, 5.1%-7.1%) and oxygen was 19.8% (95% CI, 19.5%-20.1%) vs 12.4% (95% CI, 11.2%-13.5%) at the same points in the safety device and control groups, respectively.

Conclusions and Relevance  A user-carried avalanche safety device that delivers airflow from avalanche debris to the user’s airways without requiring supplemental oxygen delayed critical hypoxemia and hypercapnia during simulated critical burial.

DOI: 10.1001/jama.2025.16837

Source: https://jamanetwork.com/journals/jama/fullarticle/2839664